Broken Bay Bridge bolt repairs are finished

By Lisa Vorderbrueggen Contra Costa Times

OAKLAND -- In a quiet close to a tumultuous chapter, contractors on the new Bay Bridge on Wednesday completed the $25 million repair of those infamous broken bolts that nearly derailed the span's opening on Labor Day.

Just before noon, crews tightened the last of the 142 concrete-encased steel rope tendons inside the massive fabricated steel saddles. They replace the clamping force lost when anchor rods snapped in critical seismic stabilizers just east of the main tower.

After the tendons were adjusted to the proper tension using hydraulic jacks and their casings grouted and capped, contractors removed the temporary steel shims inserted into the stabilizers last summer to make the bridge safe enough to open during repairs.

Crews prepare to complete work on the new eastern section of the Bay Bridge Tuesday, Dec. 17, 2013, tightening down the last 10 of the 142 concrete-encased steel tendons designed to replace the clamping force lost when giant anchor rods snapped in critical seismic stabilizers last March. (Karl Mondon/Bay Area News Group)

While the embarrassing bolt repair chapter may be over, the book on the Bay Bridge is far from finished, with hearings scheduled in Sacramento early next year into why the span was a decade late and cost nearly fivefold what engineers estimated.

Wednesday's announcement comes three weeks after engineers originally estimated the work would be done but several weeks ahead of Caltrans' latest schedule.

Completion means the $6.4 billion span's structural protections against collapse or major damage in the next big earthquake are fully operational, said Caltrans field engineer Pamela Gagnier during a Tuesday boat trip out to the pier where the repairs were done.

Engineers designed the bridge to meet California's most stringent seismic standard: Remain open or reopen within hours following the strongest temblor engineers predict in the next 1,500 years.

But when contractors pulled out the shims, motorists didn't feel or see a thing.

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Broken Bay Bridge bolt repairs are finished